 Elsewhere the several groups of traders and artisans made of their gilds all-powerful agencies for organising joint action among classes of commons united by a trade interest, and the history of the towns becomes the history of the struggle between the gilds which captured control of the council and the gilds which were excluded therefrom.Many municipal revolutions took place, and a large number of constitutional experiments were tried all over the country from the 13th century onward.Schemes which directed a gradual co-optation, two to choose four, these six to choose more, and so in widening circles from a centre of officialdom, found much favour throughout the Middle Ages.